1. Field of the Invention
The present invention relates generally to the field of pet supplies, more particularly to cat (kitty) litter boxes, and still more particularly to self-cleaning cat (kitty) litter boxes.
2. Background Discussion
According to a 1999 poll (reportedly having a +/xe2x88x923% probability of error) conducted by the American Pet Association, 31.2 million United States"" households, out of a total of 102.8 million households, had at least one cat as a pet, with cats outnumbering dogs by 74,894,580 to 61,542,900.
As is well known to cat owners, most cats can be trained or taught to use specific places in the home for their toilet activities. These specific places are commonly provided with boxes (or trays) holding cat or kitty litter that is readily available in pet stores and most supermarkets.
So far as is known to the present inventor, so called self-clumping cat litter was first marketed in about the early 1990""s. When a cat urinates or defecates into such type of cat litter, the moisture causes the contacted litter to aggregates into clumps that quickly harden. These hardened clumps containing the cat""s urine or excrement can then be removed from the litter box by the cat owner, leaving substantially clean litter in the box for the cat""s subsequent use.
The most common and inexpensive implement for removing these hardened clumps of cat litter are hand-held, slotted metal or plastic scoops. Although effective in removing the clumps of cat litter from a litter box, the use of such manual scoops requires constant personal attention to the litter boxes to keep them clean. Otherwise many or most cats will either refuse to use the litter boxes or else will paw the hardened clumps from the litter boxes onto the floor, in the process usually scattering loose cat litter all over the floor, thereby creating a messy clean-up problem. Moreover using a hand-held scoop to clean out cat litter boxes is understandably a disagreeable task for many if not most cat owners, since the individual doing the scooping must have his or her face close to the litter box and is thereby exposed to unpleasant smells.
The above-described forming of hardened clumps of cat litter containing a cat""s urine or excrement lends itself to automated cleaning of litter boxes. This type of litter box is commonly referred to as a self-cleaning or self-collecting litter box. Exemplary of such self-cleaning litter boxes are those disclosed in the below-cited United States Patents.
U.S. Pat. No. Re. 36,847, issued Sep. 5, 2000 to Michael A, Waters, for example, discloses a self-cleaning cat litter box that utilizes a multi-toothed element or comb that is automatically moved linearly through a fixed litter tray to rake clumped litter from the litter tray into a waste receptacle. U.S. Pat. No. 6,378,461, issued Apr. 30, 2002 to Arnold Thaler also discloses an automated self-cleaning cat litter box that utilizes a comb automatically moved linearly through a fixed litter box to rake clumped litter from the litter tray into a waste receptacle. U.S. Pat. No. 5,048,465, issued Sep. 17, 1991 to Angelo Carlisi, discloses still another automated self-cleaning cat litter box that utilizes a comb that is moved through a fixed litter box to rake clumped litter from the litter and deposit the clumped litter into a waste receptacle.
U.S. Pat. No. 5,931,119, issued Aug. 3, 1999 to Ofer Nissim et al., discloses an automated self-cleaning cat litter box that utilizes a horizontally revolving litter tray having a retractable comb that accumulates clumped litter as the litter tray revolves under the comb. The comb is periodically pivoted upwardly to discharge the clumped litter into a waste receptacle. U.S. Pat. No. 6,401,661, issued Jun. 11, 2002 to Richard H. Emery, also discloses an automated self-cleaning cat litter box that utilizes a horizontally revolving litter tray having a fixed comb that collects clumped litter from the litter as the litter tray revolves under the comb. A screw mechanism then removes the clumped litter from the comb to a waste receptacle.
U.S. Pat. No. 5,749,318, issued May 12, 1998 to Gerard Barbot, et al., discloses a self-cleaning litter box that utilizes a screen-type conveyor belt in communication with litter in a litter tray to separate clumped litter from clean litter, the clumped litter being discharged into a waste receptacle and the clean litter being returned to the litter tray. U.S. Pat. No. 5,460,122, issued Oct. 24, 1995 to Johann C. Reimartz, discloses an automated self-cleaning cat litter box incorporating a movable litter tray floor that removes used litter from the litter tray and discharges it into a receptacle as the floor is moved in one direction, and causes fresh litter to be discharged from a litter reservoir into the litter tray as the floor is moved in the opposite direction.
Although the disclosed automatic self-cleaning cat litter boxes may be reasonably useful, most, principally the comb-type self-cleaning litter boxes, that have been commercially available, for example, in pet stores, have a disadvantage that the combs, especially the movable combs, tend to become with clogged with or by clumped litter to an extent that their operation is adversely affected.
For this and other reasons, a principle objective of the present invention is to provide an automatic self-cleaning cat litter box apparatus that is both effective and reliable in operation.
In accordance with the present invention, there is provided a self-cleaning cat litter box apparatus that comprises a litter tray for containing a quantity of cat litter, a waste bin and a mesh basket sized for having a lower basket regions received into the litter tray. The basket is pivotally mounted relative to the litter tray for pivotal movement between a lowered position in which a lower region of the basket is immersed in cat litter contained in the litter tray and a raised, tilted position in which cat waste-containing clumped litter picked up in the basket from the litter in the litter tray is gravity dumped into the waste bin.
Included is a reversing electric basket pivoting motor connected for causing the pivoting of the basket between the lowered and raised, tilted positions. A basket frame is included to which the basket is attached, A driven gear is fixed to the basket frame, and a drive gear is connected to the electric basket pivoting motor and is in driving relationship with the driven gear.
The apparatus further comprises control means configured for causing the electric basket pivoting motor to rotate in one direction to pivot the basket from the lowered position to the raised, tilted position and for then causing the electric basket pivoting motor to rotate in an opposite direction to pivot the basket from the raised, tilted position back to the lowered position. Starting of the control means is responsive to a cat entering and subsequently leaving the litter tray, the starting being delayed for a predetermined time interval of at least about one minute after a cat enters and subsequently leaves the litter tray, and is cancelled in response to a cat entering the litter tray within the predetermined time interval.
Preferably there is included an electric basket oscillating motor connected for causing the basket to oscillate back and forth relative to the litter tray and the control means are configured for causing the basket oscillating motor to oscillate the basket back and forth relative to the litter tray when the electric basket pivoting motor starts pivoting the basket from the lowered position toward the raised, tilted position and again when the electric basket pivoting motor subsequently pivots the basket back to engagement with the litter contained in the litter tray, so as to facilitating both the raising the lower regions of the basket through litter contained in the litter tray and the subsequent immersion of the lower regions of the basket into litter contained in the litter tray.
A waste bin door is hinged for pivotal movement between a closed position covering the waste bin and an open position uncovering the waste bin, the door being connected for pivoting from the closed position to the open position as the basket is pivoted from the lowered position to the raised, tilted position and for pivoting from the open to the closed position as the basket is pivoted from the raised, tilted position back to the lowered position.
More specifically, a self-cleaning cat litter box apparatus comprises a litter tray for containing a quantity of cat litter, a waste bin having an open top, a rigid basket frame and a mesh basket having a lower region sized for being received into the litter tray. The basket is attached to the basket frame to form a basket assembly that is hinged relative to the litter tray for pivotal movement between a lowered position in which the lower region of the basket is immersed in cat litter contained in the litter tray and a raised, tilted position in which cat waste-containing clumped litter picked up by the basket from litter in the litter tray is gravity dumped from the basket into the waste bin.
A reversing electric basket assembly pivoting motor is connected for causing the pivoting of the basket assembly between the lowered and raised, tilted positions, and an electric basket assembly oscillating motor is connected for causing the basket assembly to oscillate back and forth relative to the litter tray.
Included are control means configured for causing the electric basket assembly pivoting motor to rotate in one direction to pivot the basket assembly from the lowered position to the raised, tilted position and for then causing the electric basket assembly pivoting motor to rotate in an opposite direction to pivot the basket assembly from the raised, tilted position back to the lowered position, a starting of the control means being responsive to a cat entering and subsequently leaving the litter tray after a time delay period of at least about one minute after a cat, the starting of the control means being cancelled in response to a cat entering the litter tray within the delay period. The control means are also configured for causing the basket assembly oscillating motor to oscillate the basket assembly back and forth relative to the litter tray when the electric basket assembly pivoting motor starts pivoting the basket assembly from the lowered position toward the raised, tilted position and when the electric basket pivoting motor subsequently pivots the basket back close to the lowered position, thereby facilitating both the lifting of the basket lower region up through litter contained in the litter tray and the subsequent immersion of the basket lower region into litter contained in the litter tray.
The apparatus further includes a waste bin door hinged for pivotal movement between a closed position covering the waste pin and an open position uncovering the waste bin, the door being connected for pivoting from the closed position to the open position as the basket assembly is pivoted from the lowered position to the raised, tilted position and for subsequently pivoting the door from the open to the closed position as the basket assembly is pivoted from the raised, tilted position to the lowered position.
Still more particularly, a self-cleaning cat litter box apparatus comprises a base portion; a litter tray configured for containing a quantity of cat litter, the tray having a bottom and being removably installed in the base portion; a litter waste collecting and disposing portion having a top and sides; and a basket assembly, including a basket frame and a wire mesh basket attached to the basket frame. The basket has a top, a bottom, sides and first and second ends. The basket frame is hinged, along a basket frame hinge line, adjacent the basket first end to the top of the litter waste collecting and disposing portion. Lower regions of the basket sides and second end are preferably bowed outwardly and the basket first end is preferably angled toward the basket second end.
A waste bin is removably received in the base portion portion, said waste bin having an open top and including a waste bin door hinged along a waste bin door hinge line to the top of said litter waste collecting and disposing portion, the waste bin door hinge line being parallel to the basket frame hinge line and being located so said door is close to said basket first end. A basket assembly pivoting motor is connected for pivoting the basket assembly through a basket assembly pivoting angle between a first, litter engaging position and a second, elevated, cat waste-containing clumped litter dumping position. The basket assembly pivoting motor is also connected for causing at least substantially simultaneous pivoting of the waste bin door through a door pivoting angle between a first, closed position covering the waste bin open top and a second, open position uncovering the waste bin open top thereby enabling waste dumping access to the waste bin.
Means are included for mounting the litter waste collecting and disposing portion onto the base portion so that when the basket assembly is in the first, litter engaging position, the bottom of the basket is adjacent the bottom of the litter tray and is beneath cat litter contained in the tray.
Control means are further included that are responsive to a cat entering and subsequently exiting the litter tray for enabling the basket assembly pivoting motor to pivot the basket assembly from the first, litter engaging position to the second, cat waste-containing clumped litter dumping position and to pivot the waste bin door from the first, closed position to the second, open position, thereby causing cat waste-containing clumped litter picked up by the basket from litter contained in the litter tray to be gravity dumped from the basket into the open waste bin, and thereafter for causing the basket assembly pivoting motor to pivot the basket assembly back to its first, litter tray engaging position and to pivot the waste bin door back to its first, closed position.
An oscillation-causing electric motor is connected for causing oscillatory movement between the litter waste collecting and disposing portion and the base portion in a longitudinal direction that is orthogonal to the basket frame hinge line as the basket assembly is being pivoted from its first litter engaging position and as the basket assembly is being pivoted back to its first litter engaging position, thereby assisting lifting of the basket through cat litter contained in the litter tray and thereby subsequently assisting the bottom of the basket to immerse into cat litter contained in the litter tray. The oscillation-causing motor preferably causes oscillatory motion of the litter waste collecting and disposing portion through a distance of at least about one inch while the base portion remains stationary.
It is also preferred that the starting of the control means is delayed for a period of at least about one minute after a cat enters and subsequently leaves the litter tray to provide for litter clumping, and wherein the starting of the control means is cancelled in response to a cat entering the litter tray during said delay period.